In spite of increasingly stricter government regulations and ongoing efforts in the meat, fish and poultry industries, outbreaks of illnesses caused by food-borne bacteria continue to occur on a regular basis. In 1999 alone, 25 people in the United States died as a result of consuming contaminated meat or poultry products. The presence of any illness-causing bacteria on ready-to-eat (RTE) and other precooked meat, poultry, and fish products (e.g., sliced or sliceable ham, beef, or turkey logs or whole muscle products, Virginia hams, oven-roasted turkey, spiral honey-baked hams, etc.) is of particular concern because these products typically are not recooked or sufficiently reheated prior to consumption.
The threat posed to public health and safety by food-borne pathogens is extremely wide-spread and the economic impact of even a single outbreak can be staggering. Recently, one company issued a voluntary recall of approximately 16.7 million pounds of RTE turkey and chicken products because of possible contamination problems at just one of the company's processing facilities. It is reported that possible contamination problems were traced to the facility following the occurrence of certain illnesses identified by state health departments. The recalled products had been distributed nationwide and to some foreign countries.
Examples of particularly serious bacterial contaminants include Listeria, salmonella, and E-coli. These contaminants are especially problematic when dealing with RTE and other precooked meat, poultry and fish products and are often present in processing environments in spite of diligent efforts to eliminate them. Listeria monocytogenes, for example, is tolerant to salt, can grow at low temperature, has a high heat tolerance, and can form stubborn biofilms on processing surfaces.
When dealing with RTE and other precooked products, the risk of contamination is particularly high after cooking and prior to completing the final packaging process. Such meat, poultry, and fish products are typically cooked to an internal temperature of at least 160° F. so that, at the end of the cooking process, no listeria, salmonella, or E-coli should be present. However, prior to packaging, the cooked product will typically be chilled or otherwise allowed to cool to an internal temperature of about 40° F. or less and can be contaminated by airborne and other pathogens and/or bacteria present in the air, on conveyor surfaces, on processing equipment, in condensate drippage, or on the hands of workers in the processing area.
In response to continuing outbreaks of food-borne illnesses, governmental regulatory agencies continue to impose stricter regulations. USDA and FDA authorities have now established zero tolerance requirements for listeria monocytogenes and salmonella in all RTE food products.
Unfortunately, as evidenced by the continuing occurrence of illnesses and deaths from food-borne bacteria, many current industry practices and procedures are not sufficiently reliable and are inadequate to meet the zero tolerance requirements now imposed by regulatory agencies. Current procedures commonly consist of maintaining the cooked product in a “clean” environment (a “clean room”) and conveying the product along a critical control path designed to prevent bacteria from reaching the product surfaces. In an effort to keep the processing environment clean, the air within the clean environment is typically filtered and operators are instructed to wash all contact surfaces between shifts and to wash their hands each time they enter the clean area.
It is thus apparent that a need presently exists for a process which will consistently and effectively kill surface bacteria present on food products, particularly on RTE and other precooked meat, poultry, and fish products, and will meet and exceed all governmental regulatory requirements. A need particularly exists for such a process which will not alter the surface characteristics or internal characteristics of the products in any significant way.